void main() {

  ANSEL = 0;                          // Configure AN pins as digital
  TRISA = 0;                          // Set PORTA as output
  PORTA = 0;                          // Initial PORTA value
  OSCCON = 0x60;                      // 4 MHZ


        while(1)         // forever
                {
                PORTA = 0b00001000;
                Delay_ms(500);
                PORTA = 0b00000100;
                Delay_ms(500);
                PORTA = 0b00000010;
                Delay_ms(500);
                PORTA = 0b00000001;
                Delay_ms(500);
                }
             }